Blast-air regulation for diesel engines



July 16, 1929.

B. V. E. NORDBERG BLAST AIR REGULATION FOR DIESEL ENGINES Original Filed,0ct. 6, 1926 ammmibd c 3771220 1221 .7Vbra 5e7y' Puma July 16, 1929.

outrun STATES PAENT OFFICE.

BRUNO V E. NOBDBERG, OF MILWAUKEE, WISCONSIN, ASSIGNOR "10 NORDBERG MANU- FACTURIN G COMPANY, 01?. MILWAUKEE, WISGONSIN, A. CQRCPORATION OF WIS- cous n.

BLAST-AIR REGULATION FOR DIESEL ENGINES.

Application filed. October 6, 1926, Serial No 139,943. Renewed. June 3, 1929.

This invention pertains to Diesel engines and relates more particularly to an improved means for supplying and controlling the blast air employed for the injection of fuel. v It is a desideratum in the operation of Diesel engines to control the air blast employed to inject or atomize the fuel charge and to have the air maintained and delivered at the proper pressure. according to the speed of the engine and the workimposed thereon. The advantages of Diesel. engines make them most useful in such work as private industries and central power stations where wide fluctuations in load are common. These fluctuations arise very quickly and in a Diesel engine employing air "for the in jection of fuel it is necessary to vary the blast air pressure to suit such fluctuations in order to bring about the best working conditions. In most instances, the variation of load without changing the blast air pressure brings about violent fluctuations in speed and incomplete combustion which of course is very objectionable. The apparatus or mechanism hereinafter set forth obviates such diflicultiesin regulation, with resulting better fuel economy, and likewise prevents or lessens the hunting action of engine which usually comes about at no load, or very light loads. My invention also obviates great deal of maneuvering by the operator, which under present practice is generally necessary, the engine practically taking care of itself. L

35 One embodiment of my invention by way of illustration is disclosed in the annexed drawings wherein:

Figure 1 is a view, more or less diagrarrn matic, oil so much out an air storing and delivering mechanism tor Diesel engine as is newssary to an understanding of my invention, and w Figure 2 is a detail sectional view the balanced valve which is employed to efiect,

delivery of the proper quantity of blast air to suit working conditions.

In the drawings, 1 denotes an air compres p sor shown in the instant case as of the three stage type and provided with automatic valves-though any type of valve may be employed. The compressor may derive ts power from the cgoank shaft oi the engine .(or other source); and delivers the highly in conjunction with "the engine governor, the

compressed air through a'pipe2 to a reser- V011. or bottle 3 of relatively large capacity.

Air enters the compressor through a pipe 4 the outer end whereof terminates in the housing 5 of a suitable throttling mechanism.

to its upper end a piston 12 working in a cylinder 13 the upper end of which is vented as at 1a. A spring 15 is interposed between the lower end of the cylinder 13 andan adj ustahle collar 16 mounted upon the rod 11. A pipe 17 extends from the bottle or reservoir 3 into the lower portion of the cylinder 13 beneath the piston 12 and the piston is normally forced upwardly against the stress 1 of the spring 15 by the compressed air which passes from the reservoir or bottle 3. lit will thus be seen that the valve 6 will be moved toward or from its seat 7 to choke the air inlet to the compressor, or away from its seat, to allow more air to enter, according as the pressure in the reservoir rises or falls. By adjusting the spring 15 the degree and time of opening of the valve 6, as well as the limits of pressure fluctuations, may be regulated to suit working conditions.

Extending from the reservoir or bottle 3 is a pipe or,conduit 18, said pipe being secured in the lower portion of a valve housing or casting .19.

The blast pipe leading to the fuel injecting mechanism, which latter is not shown, is denoted. by 26* and is secured in the'member 19 at a point. above the entrance of the pipe 18. The pipe 18 opens into a chamber 21 formed in the member 19, said chambercommunicating with the pipe 20 through an opening 22, formed in, the block or casting above the chamber 21 through a valve seat or ort 23 and a second chamber 24. The valve seat 23 and the chamber 24 are formed in the lower end of a bushing 25 seated within the upper portion of a bore formed in the member 19, said bushing at its lower end bearing upon a shoulder 26 formed about the passage 22 the bushing also being provided witha collar 27 which bears upon a second shoulder 28 formed in the upper portion of the bore. The bushing is held in place by an externally threaded sleeve 29 which is screwed into the upper enlarged portion of the bore and takes convenient and satisfactory way of produc ing the valve seat and the guides for the valve. The latter is shown in the form of a rod or stem 34 which extends through the bushings making as near a frictionless con tact as possible in order that it may be freely moved. Lap joints are employed to prevent leakage of the air outwardly around each end of the valve though if desired, other means for effecting this may be employed.

It is to be noted that the pressure in chamber 21 works on exactly the same diameter in either direction so that this portion of the Valve is absolutely balanced. The chamber 24, which is always at a lower pressure than. chamber 21, also acts on similar areas at either end of the chamber so as to exactly balance this portion of the valve, the consequence being that the position of the governor hereinafter referred to, is in nowise effected as there is none or very little additional work imposed upon it.

It will also be noted that the Valve 34 is reduced in diameter where it passes through the chamber 24 and the seat 23 is shown as tapered and enlarging toward the intake end or toward the chamber 21.

A nut 35 is secured to the lower end of the valve which is merely a means of protection to prevent the valve from blowing out from the casing should it become unbalanced for some T638011 01 another.

The upper end of the stem is also threaded and a nut 36 is screwed thereon, the nut bearing against a cap-piece 37 between which, and a second cap-piece or washer 38, there is interposed a spring 39. By turning the nut 36 the tension of the spring may be varied as desired or necessary. The upper end 40 of the valve stem extends freely into an opening formed in the lower end of an adjustable link 41 the upper end of which is pivotally connected to a lever 42, the elevation or compression of which is controlled by the engine governor 43. Preferably, this lever will be mounted upon a fulcrum capable of adjustment so as to vary the ratio of lengths F a and b of said lever. Fulcrum 44 may be fixed and point 45 changed for varying ratios, shifting the valve body 19 to suit. governor in addition to functioning in its regular manner, that is, increasing or decreasing the amount of fuel pumped to the engine, will handle the blast pressure adjusting it to the required amounts for the best operating conditions. The amount of lift of the valve 34 is determined experimentally and can be varied by changing the ratio of the lengths (I; and b on the governor lever 42. The position and setting of the valve with reference to its seat to insure the correct and required amount of air flow therethrough may be taken care of by adjustment of the length of I the link 41. The arrangement just described. forms a From the foregoing it will be noted that the valve 34 is positively actuated and moved The i from its seat by the governor, the connection between the lever 42, the link 41 and the up per end of the valve being direct and hence the valve will be moved positively away from its seat by the action of the governor. It is also to be noted that the valve seat 23 is tapered and as the valve is moved downwardly the area through which the air may flow is increased and this in proportion to the down ward movement of the valve.

As a greater or less amount of air is drawn from the reservoir or bottle 3 it becomes apparent that the pressure fluctuations in this bottle would effect the pressure in the air line 20 leading to the fuel valves. The arrangement above described effects satisfactorily the automatic regulation of the air pressure in the bottle. The spring loaded piston or plunger 12, which is subject to the pressure in the bottle 3, maintains the requisite pressure in said bottle. The strength of the spring 15 can be varied and the scale of the spring can be chosen so as to bring about as great or as little fluctuation in pressure in the bottle or reservoir 3 as is desired.

It is to be understood thatI do not desire to limit myself to the relative location of the chambers 21 and 24 as above described. The position of these chambers may be reversed, the chamber 21 being above the chamber 24 provided it is so located with reference tothe governor as to produce the desired results. It will be appreciated, of course, that under such conditions the valve seat will likewise be reversed and the point of attachment of the link 41 to the lever 42 will Be to the left of the fulcrum 44. Inasmuch as this is mere reversal of parts it is thought unnecessary to specifically illustrate the same.

From the above description it will be noted that the valve, which is balanced as to pressures and is nearly frictionless in its operation as possible, is handled directly by the governor. By reason of this direct action an almost instantaneous change in the line leading to the fuel line is realized; in other words, the fluctuations of pressure are directly in control of the governor. The valve being an absolutely balanced one it offers no appreciable resistance to the governor and therefore avoids many complications existing in the prior art both as to structure and operation.

What is claimed is:

1. In an air blast regulator for Diesel engines, the combination of an air supply under pressure; a blast line communicating therewith; a valve located in the line; a balanced valve working in conjunction with the seat to vary the area of opening through the seat and thus controlling the passage of the air therethrough; the engine governor; and connections between the governor and valve for directly controlling the valve in response to movements of the governor efi'ected by operating conditions of the engine. .1

2. Apparatus as specified in claim 1 wherein the connection between the governor and valve takes the form of a link adjustable as to length.

3. In an air blast regulator for Diesel engines, the combination of an air compressor; a reservoir into which said compressor discharges; an intake valve for the compressor;

means subject to control by the degree of pressure within the reservoir for regulating said intake valve whereby the intake of the compressor will be automatically regulated; an air blast line leading from the reservoir; a balanced valve located in the line; the engine governor; and direct connections between the governor and the balanced valve for directly and positively controlling the latter.

4. In a blast air regulator for .Diesel engines, the combination of an air reservoir; means for maintaining air therein at a substantially constant pressure; a blast line communicating with the reservoir; a valve seat located in the line; a balanced valve working in conjunction with the seat to control the volume of air passing through the line; the engine governor; and connections between the governor and the valve for directly controlling the position of the valve in response to movements of the governor efi'ected by operating conditions of the engine.

5. In air blast systems for Diesel engines, the combination of an air compressor; an air reservoir into which it discharges; a loaded throttling valve for the intake of the compressor; means subject to the air pressure obtaining in the reservoir for moving said valve toward closed position; a blast line extending from the reservoir; a balanced valve interposed in said line; the engine governor; and direct connections interposed between said last named ualve and the governor for varying the position of the valve in response to change of position of the governor.

6. In a blast air regulator for Diesel engines, the combination of an air reservoir;

means for maintaining the requisite pressure therein; a blast line leading from the reservoir; a valve housing interposed in said line, said housing having an opening extending therethrough interrupted by spaced inwardly projecting shoulders forming a chamber therebetween, said space being in communication with one section of the blast line; a guide secured in one end of the opening; a second guide secured in the opposite end of the opening, the inner ends of the guides respectively abutting the shoulders and terminating adjacent the chamber, said second guide having a valve seat formed therein at its inner end, and likewise having a chamber outward of said seat which is in communication with the other section of the blast line; a valve mounted for endwise movement in the guides, the valve being reduced in diameter at that portion which extends through the chamber of the second guide; an engine governor; and a direct connection between said governor and the valve.

7. The apparatus as specified 1n clalm 6 wherein the valve guides are held in place by bushings threaded into the housing and taking attheir inner ends against collars formed on the guides, the bushings being otherwlse out of contact with the guides.

in one direction; and a link interposed be-.

tween the governor and the adjacent end of the, valve serving, when moved by the governor, to move the valve in the opposite direction.

In testimony whereofl have signed my name to this specification.

'BRUNO v. E. NORDBERG.

CERTIFICATE OF CORRECTION.

Patent No. 1,721,032. Granted July 16, 1929, to

BRUNO V. E. NORDBERG.

it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3. line 11, after the word "valve" insert the word "seat"; and that the said Letters Patent should he read with this correction therein that the same may conform to the record of the case in the Patent Ottice.

Signed and sealed this 13th day of August, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

